The proposed experiments will examine changes in arterial pressure, cardiac output, and total peripheral resistance during the development of perinephritis hypertension in sheep. Additional studies are designed to investigate the possibility that a humoral non-renin pressor substance might play role in experimental renal hypertension in animal models. BIBLIOGRAPHIC REFERENCES: Johnson, J. A., J. O. Davis, R. W. Gotshall, T. E. Lohmeier, J. L. Davis, B. Braverman, and G. E. Tempel. Evidence for an intrarenal beta receptor in the control of renin release. Am. J. Physiol. 230: 410-418, 1976. Johnson, J. A. and J. O. Davis. Effect of estrogens on renal sodium excretion in dogs. In: Hypertension in Pregnancy. (Proceedings of an International Symposium on Hypertension in Pregnancy; University of Chicago, Sept., 1975). In Press.